Medium · published January 22, 2026
The _.unset and _.omit functions in Lodash are vulnerable to prototype pollution. An attacker can pass crafted paths which cause Lodash to delete methods from global prototypes. The issue permits deletion of properties but does not allow overwriting their original behavior. The issue is patched from 4.17.23 to 4.18.0 depending on the package: lodash, lodash-es, and lodash-amd in 4.17.23, and the standalone lodash.unset and lodash.omit packages in 4.18.0.
| Product | Versions | Fixed in |
|---|---|---|
| lodash/lodash | ≥ 4.0.0, < 4.17.23 | 4.17.23 |